Don't give up too soon, 13 letters
Persevere, like a golfer?, 13 letters
Persist to completion, 13 letters
Have no quit in you, 15 letters
Avoid arguments, literally, 11 letters
Al Green Let's ___, 12 letters
Don't touch that remote!, 9 letters
Keep it where it is, 9 letters
Pre-commercial phrase, 9 letters